The current invention relates to a process and a device for protecting a turbocharger of an internal combustion engine against being destroyed by an excessive charger speed.
As can be seen from MTZ, Motortechnische Zeitschrift [Motor Technology Journal], 53 (1992) 10, pp. 454 to 462, with increasing altitude and therefore decreasing ambient pressure, i.e. decreasing air pressure, the required charging pressure of a turbocharger is only achieved with an increase in the charger speed. To this end, the waste-gate on the exhaust side of the turbocharger is more closed and consequently, the turbine is acted on with a larger quantity of exhaust. However, so that decreasing ambient pressure does not lead to an excessive increase in the charger speed, which would destroy the turbocharger, the atmospheric pressure is measured with the sensor and the charging pressure reference value for the regulation is reduced as a function of this.
According to DE 43 02 339 A1, the maximum permissible fuel quantity to be injected is predetermined based on operating parameters such as temperature and pressure. In an internal combustion engine equipped with a charger, preferably a self-igniting engine, the charging air temperature is predetermined based on the ambient temperature, the atmospheric pressure, and the charging pressure.